Exciting-alternator.



No; 7|7,507. Patented Dec. 30, I902".

E. w. RICE, 18.

EXCITING ALTERNATUBS.

'Application filed June 6 1902.)

(N0 Model.)

Witn esses. I lnventgr Edwin W Rlce Jr. #ZV KA c. 1n: nomgmznqm. PHOTO-040., wnsumo-ron. u I

UNITED STATES PATENT OEEIcE.

EDIVIN W. RICE, JR, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GEN- ERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

EXCITING-ALTERNATOR.

SPECIFICATION forming part of Letters Patent No. 717,507, dated December 30, 1902.

Original application filed June 8, 1900, Serial No. 19,529. Divided and this application filed June 6, 1902. Serial No.110,429. (No model.)

To all whom, it may concern:

Be it known that I, EDWIN W. RIcE, Jr., a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Exciting-Alternators, (Case No. 2,953, division of my application, Serial No. 19,529, filed June 8, 1900,) of which the following is a specification.

My present invention relates to the regulation of dynamo-electric machines, and more particularly to the regulation of an alternating-current generator or other source of energy feeding current through a reactive transmission-line to some receiving-circuit.

In carrying out my invention I set up at the generating end of the line an electromotive force, which is arranged to vary in the same proportion as the variation of electromotive force at the end of the line, and the electromotive force which I thus set up I employ to regulate the impressed electromotive force of the generator.

My invention will better be understood by reference to the following description, taken in connection with the accompanying drawing. Its novel features I will point out in the claims appended hereto.

In the drawing I have shown a generator at 1, connected to and feeding reactive transmission-lines 3 I. In the particular embodiment of the invention which I have herein shown this generator is provided with two field-windings, (indicated, respectively, at 5 and 6,) these field-windings being arranged to act in opposition to each other. The winding 5 is excited from any suitable source of direct current-such, for example, as an exciter 7-the electromotive force of which may be regulated in the usual manner by means of a field-rheostat. The winding 6, which I term a regulating-winding, is supplied with current from the direct-current side of a rotary converter 8, the alternatingcurrent terminals of which are connected in series with two transformer-secondaries 9 and 10, the primary 11 of one of the transformers being shunted about a combination of resistance and inductance 12, representing in miniature these factors in the trans mission-line, while the primary 13 is shunted across the transmitting end of the lines 3 4c. In this case the transmission-line is supposed to contain only resistances and inductances, for which reason I have shown at 12 a combination of resistances and inductances having the same relation to each other as the resistances and inductances in the transmission-line, but on a smaller scale. It will be evident, however, that if the transmissionline contains capacity the arrangement of the artificial line 12 may be varied to correspond. Owing to the fact that the artificial line 12 represents the transmissionline in miniature, it will be evident that the electromotive force or drop between its terminals will on a small scale represent the actual drop in potential in the transmissionlines. By combining the electromotive force set up in the secondary 9 with the electromotive force set up in the secondary 10 it will be evident, if suitable ratios of transformation are chosen in these transformers, that the resultant electromotive force will represent that which exists at the receiving end of the line. The electromotive force of the secondary 9 should have the same relation to that of the secondary 10 as the drop in the line has to the impressed electromotive force.

The resultant electromotive force derived from the secondaries 9 and 10 being impressed upon the rotary converter 8 gives rise to a direct current in the regulatingwinding 6, which varies in proportion to the variation of electromotive force at the re ceiving end of the line. The winding 6 being connected into circuit, so as to be in opposition in its effect to the winding 5, will decrease the resultant field strength when the electromotive force at the receiving end of the line rises and increase the field strength when the receiving eleotromotive force falls, thereby causing the electromotive force of the generator to vary in such a manner as will preserve a constant electromotive force at the receiving end of the line or at some other selected point on the system.

Instead of using a rotary converter for the purpose specified I may, if found desirable, employ a rectifying-commutator, and this, as

rent dynamo-electric machine, lines extending therefrom, series and shunt transformers connected to said lines, a circuit connecting the secondaries of said transformers in series, a rotary converter fed from said circuit, and a field-winding of said machine traversed by current from said rotary converter.

In witness whereof I have hereunto set my hand this 4th day of June, 1902.

EDWIN WV. RICE, JR.

Witnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

